Method and apparatus for producing a voluminous yarn with uniformly spaced bindings



YARN

1968 H. GEMEINHARDT ETAL METHOD AND APPARATUS FOR PRODUCING A VOLUMINOUS WITH UNIFORMLY SPACED BINDINGS 2 Sheets-Sheet 1 Filed June 20, 1966 FIG. I

INVENTORS: HERMANN GEMEINHARDT GUNTHERHSCHATZ BY BRUCHER HANS Dec. 24, 1968 H. GEMEINHARDT ET AL 3,417,445

METHOD AND APPARATUS FOR PRODUCING A VOLUMINOUS YARN WITH UNIFORMLY SPACED BINDINGS Flled June 20 1966 2 Sheets-Sheet 2 I FIG. 3

FIG. 7

FIG. 5

FIG. 4

INVENTORS: HERMANN GEMEINHARDT GUNTHER SCHATZ HANS BRUCHER ATT'YS United States Patent 10 Claims. (c1. 2s 1 ABSTRACT OF THE DISCLOSURE Method and apparatus for uniformly oscillating a yarn conducted between two fixed points in a secondary resonance chamber under the influence of a jet of gas impinging perpendicularly on the normal straight line path of the thread between the fixed points and entering into a primary resonance chamber arranged behind and in fluid communication with the secondary resonance chamber, thereby producing uniformly spaced bindings along the length of the yarn.

This invention relates to a method and apparatus for the production of loose, bulky or voluminous yarn having uniformly spaced bindings along its length. More particularly, the invention is concerned with a specific method and means of treating a continuous multifilament crimped yarn so as to insert bindings at uniformly spaced distances capable of being selectively varied, the individual filaments being in close or solid contact at the binding points while being relatively loose or separated between such binding points, thereby retaining substantially the same looseness or bulkiness as that of the original yarn.

It is known that yarns composed of individual continuous filaments can be treated with a stream of gas in such a manner that the individual threads or filaments become very closely intertwined or interlaced in solid contact with each other. The resulting yarn is not voluminous and exhibits very little elasticity, but instead the treated yarn behaves in a manner similar to that of twisted threads. Such compact interlaced yarn is essentially intended as a substitute for conventional twisted yarns, and is therefore distinguished from so-called bulk or textured yarn. It is further known that a multifilament yarn can be texturized or bulked, sometimes with a crimping effect, by treatment with a high velocity fluid jet under various conditions. In this case, the treated yarn is geenrally more voluminous than the original untreated yarn.

One object of the present invention is to provide a method and apparatus for the treatment of a substantially untwisted, continuous, multifilament crimped yarn with a gas jet so as to place uniformly spaced bindings or knots along the length of the yarn while retaining most of the bulk or texturized characteristics of the original untreated yarn. Another object of the invention is to provide a method and apparatus whereby bindings or knots can be spaced along a voluminous yarn at predetermined points to yield a variety of specialty yarns having novel and useful characteristics. These and other objects and advantages of the invention will become more apparent upon consideration of the following detailed specification.

It has now been found, in accordance with the invention, that the foregoing objects can be achieved by conducting a continuous multifilament crimped yarn between two fixed points at which lateral movement of the yarn is prevented while using a yarn feed rate which is about -50%, preferably -30%, higher than its draw rate,

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and laterally oscillating the yarn between said fixed points under the influence of a jet of gas which is directed substantially perpendicular to the path of the yarn into a resonating zone such that the yarn passes through the jet of gas twice in each complete period of oscillation to produce uniformly spaced bindings along the length of the yarn.

The present invention is also directed to novel apparatus for carrying out the yarn treatment, said apparatus including nozzle means having an opening at one end to eject a jet of gas in a predetermined direction corresponding to the axis of the nozzle, and resonating means comprising a resonance floor disposed opposite the opening of said nozzle means and a jacket extending axially from said resonance floor toward said nozzle means, said jacket containing two oppositely disposed slots adapted to receive a continuous yarn in a normal straight line path therebetween which is substantially perpendicular to the nozzle axis and said jacket also containing oppositely disposed openings on a line approximately perpendicular to the straight line path between said slots. The nozzle is preferably adjustable along its axis and conically shaped to taper toward the opening thereof. At the same time, the jacket is preferably a cylindrical sleeve which ex tends from said resonance floor so that it can be positioned concentrically around the nozzle with an annular gap between the sleeve and the nozzle.

A preferred embodiment of the apparatus according to the invention is further illustrated by the accompanying drawing wherein similar parts are designated by the same reference numerals and wherein:

FIG. 1 is a schematic view of the overall method for treating the yarn in accordance with the invention;

FIG. 2 is a perspective view with portions omitted of a preferred embodiment of the yarn treating apparatus of the invention, illustrating in particular the nozzle means and resonating means in a separated position;

FIG. 3 is a side elevation view in cross-section of the same nozzle means and resonating means in a closed or operating position;

FIG. 4 is a front plan view of the same resonating means with the positions of the yarn during the gas jet treatment being indicated in a hypothetical manner; and

FIGS. 5, 6 and 7 illustrate various possible yarn configurations which can be achieved when uniformly spacing the knots or bindings along the yarn by the method of the invention. 7 Referring now to FIG. 1 of the drawing, the yarn is first introduced into a conventional crimping box 1 by means of the feed rolls 2, and the crimped yarn 3 is then led over the turning guide roller 4 through a yarn brake 5, around the guide rollers 6, 7 and 8 and finally wound or taken up on the winding reel or take-up bobbin 9. The gas jet nozzle and resonating means of the invention are contained in the housing 10 located between the turning guide rollers 6 and 7 which may also be substituted by feed and draw rollers, respectively.

As shown in FIGS. 1-4, the nozzle means for ejecting a jet of gas comprises a supply line 11 adapted to introduce gas under pressure from any suitable source into the conically tapered end portion of the head 12 so that the gas is directed from the opening 13 formed by a central bore 21 along the axis of the nozzle at a high velocity. The head or the supply line of the nozzle can be easily mounted for adjustable movement along its axis in the housing 10 in any conventional manner, e.g. =by suitably journalling the housing and sliding the cylindrical portion of the nozzle head forward or back to any desired position as indicated by the double headed arrow.

Directly opposite the opening 13 of the nozzle, there is mounted on the housing 10 special resonating means adapted to receive the continuous yarn and subject it to 3 lateral oscillation as it is drawn therethrough. This resonating means includes a conventional resonating floor 14 with a center hole 17, and from this floor there extends a jacket or cylindrical sleeve 15 containing two diametrically opposed slots 16. These slots are preferably just slightly wider than the diameter of the loose yarn being treated and sufiiciently deep to properly position the yarn between the end opening 13 of the nozzle and the resonance floor 14. Two diametrically opposed openings or bores 18 are placed about 90 from the slots 16, i.e. so that their diametric axis is substantially perpendicular to the normal straight line path of the yarn extending between the two slots. The jacket openings or bores 18 are essential in order to prevent the formation of an air or gas dam between the resonance floor and the nozzle.

Good results have been achieved in the treatment of a large number of different yarns when using the apparatus disclosed herein, and in general, it has been found desirable to employ a nozzle in which the gas jet is formed by an opening 13 of about 1 to mm., preferably about 2 to 4 him, while this opening is positioned from the resonance floor 14 at a distance of about 5 to mm., preferably 7 to 12 mm. The slots 16 in the resonance jacket may have a width of about 0.5 to 5 mm., preferably 1.2 to 4 mm., and the two jacket openings should generally correspond to a bore with a diameter of between about 0.5 and 6 mm, preferably between about 1.5 and 4.5 mm.

The resonating means is shown in greater crosssectional detail in FIG. 3 where the nozzle head 12 has been moved into an operating position to fit concentrically within the cylindrical sleeve or slotted jacket extension 15 at a predetermined distance from the resonance floor 14. A primary resonance chamber or space 19 is provided behind the resonance floor in the base member 20, for example by threading the backwardly extending cylindrical walls of the resonance floor 14 onto a correspondingly threaded portion of the base 20. The depth of the primary resonating space 19 can thus be varied to produce different resonance characteristrics as the jet of gas is directed through the bore 21 of the nozzle 12 into this space 19 through center hole 17. Likewise, it is possible to achieve a different resonance of the gas stream by varying the diameter of the center hole 17.

With the particular construction of the slotted jacket or sleeve 15 shown herein, a secondary resonance zone or chamber is formed within the jacket which causes the yarn to oscillate laterally between the two slots. This zone is approximately within the two center lines x-x, i.e. from about the midpoint between the outlet end 13 of the nozzle and the resonance floor 14 up to a distance from the resonance floor such that the depth or width of this secondary resonance zone is about one-quarter to onethird of the distance between the nozzle end 13 and the fioor 14.

It is therefore desirable to position the slots 16 and the openings 18 in the jacket 15 so as to fall within or at least directly adjacent to this secondary resonance zone. The exact shape of these jacket slots and openings is not particularly critical, and many variations can be made without departing from the scope of the invention. It is essential, however, to provide openings 18 of approximately the size indicated above in order to prevent the gas from forming a darn, since the apparatus does not properly function without these openings. However, the exact position of these jacket openings is not critical provided they are not placed far beyond the secondary resonance zone, e.g. at the upper edge of the jacket.

Likewise, the inner diameter of the jacket 15 and the corresponding size of the resonance floor 14 can be varied within wide limits, depending upon the denier of the yarn being treated, the gas velocity and similar variables. In general, good results can be achieved where this jacket diameter is about 12 to mm.

In using the apparatus of the invention, it was found that a continuous multifilament yarn being drawn at a constant velocity through the secondary resonance zone so as to be held from lateral movement at the fixed points corresponding to the jacket slots will oscillate laterally at a substantially constant frequency and form a binding or false-twist knot at regular intervals along the length of the yarn. As indicated in FIG. 4, the untwisted, bulky yarn Y enters the jacket through the upper slot 16 and is swung to the extreme left 22 at one point in its oscilla tion under the action of the gas jet. The yarn then travels to the extreme right 23 as indicated by the dotted lines while passing once through the jet stream which is directed towards the center hole 17 of the resonance floor 14. The yarn then swings back again through the jet stream to the position 22 to complete one period of oscillation. The knots or bindings 24 are formed approximately in a length of the yarn passing through the fixed slots 16 of the jacket.

It will be apparent that FIG. 4 merely represents a hypothetical or fictitious picture of the manner in which the yarn is suspended and oscillated between the jacket slots since the yarn actually travels continuously between these two points and is not held in a fixed suspension. In other words, the fixed pointsof suspension move along the yarn as it is being oscillated. In referring to a lateral oscillation of the yarn, it should be understood therefore that the yarn is actually undergoing a relatively complex undulation resulting not only from the side-to-side movement produced by the resonating gas but also from the direct impingement of the gas on the yarn as the yarn passes through the jet stream twice in each complete period of oscillation.

In acordance with the invention, it has also been found that the spacing and the individual length of the bindings depend upon a number of parameters when using specific apparatus of fixed dimensions. These parameters essentially include the yarn velocity as it is drawn through the treating zone, the tension on the yarn, the gas pressure or gas jet velocity and the distance of the gas jet opening at the outlet end of the nozzle from the resonance floor. More specifically, it was found that practically independent from the titer and number of filaments of the yarn, there is a specific gas pressure with respect to each distance of the jet from the resonance floor at which one achieves the shortest distance between the knots or bindings. Both above and below this gas pressure, the distance between the individual knots or bindings increases.

Furthermore, at a constant pressure, a stronger effect occurs as the yarn velocity decreases, i.e. the slower the yarn, the greater the number of bindings per unit length. Likewise, at a constant yarn velocity, the number of bindings per unit length increases with increasing gas pressure. Also, one achieves a shorter distance between bindings as the titer decreases.

By routine experimentation with any yarn, one can thus readily determine that gas pressure will produce the strongest effect for various distances of the nozzle or jet opening from the resonance floor. For each particular yarn, it is then possible to adjust the number of bindings per unit length by changing the gas pressure, the yarn speed and/or the spacing of the nozzle from the resonance floor.

Since the yarn length is shortened in forming the bindings or knots, it is obviously necessary to feed the yarn into the resonating means at a rate or speed which is higher than the draw rate at which the knotted yarn is withdrawn. For purposes of the present invention, the feed rate or linear velocity of the yarn should be about 540%, preferably 10-30%, higher than the draw rate.

One illustration of uniformly spaced bindings obtained by the gas jet treatment of the invention is shown in FIG. 5 and other variations are shown in FIGS. 6 and 7 where the number of bindings per unit length are increased or decreased, respectively.

The invention is further illustrated by the following examples without being limited to these examples. In each example, air at about room temperature was employed as the gas jet under a pressure of 4.5 atm. The yarn was treated with a nozzle and resonating means as shown in the drawing with the following dimensions:

Mm. Diameter of jacket 15 14 Diameter of resonance floor 14 14 Diameter of center hole 17 3.5 Depth of resonance space 19 4.0 Width of jacket slots 16 2.5 Diameter of jacket bores 18 4.0 Diameter of nozzle bore 21 3.0

Example 1 A crimped nylon-6 yarn of 1000/72 denier was fed into the jacket at a speed of 480 meters/minute and drawn and wound at a speed of 400 meters/minute. The tip 13 of the nozzle was positioned at a distance of mm. from the resonance floor 14. The treated yarn exhibited 80 bindings or knots per meter with substantially the same bulk between the bindings as the original untreated yarn.

Example 2 Using the same yarn as in Example 1, the feed speed was reduced to 240 meters/minute and the winding speed correspondingly reduced to 200 meters/minute. The resulting yarn had 152 bindings per meter.

Example 3 The yarn was again treated under the same conditions as Example 1 except that the jet opening at the tip of the nozzle was positioned at a distance of 5 mm. from the resonance floor. The number of bindings in the yarn then dropped to less than 30 per meter.

Example 4 The same conditions were followed as in Example 1 except that the jet opening at the tip of the nozzle was positioned at a distance of mm. from the resonance floor. Again, the number of bindings in the treated yarn dropped below 30 per meter.

Numerous other examples were carried out with the same apparatus using polycaprolactam and polyethylene terephthalate yarns with various deniers, number of filaments and degrees of crimping. In all cases, the number of bindings per unit length would be easily regulated either by varying the yarn speed and/ or the position of the nozzle tip with reference to the resonance floor. The bindings remained in the yarn throughout subsequent textile operations and provided the advantages of both a twisted and a bulk or voluminous yarn.

In general, any synthetic or artificial yarn such as polyamide, polyester, regenerated cellulose, or other organic thermoplastic polymer yarn can be treated by the meth- 0d and apparatus of the invention. It is even feasible to treat natural yarns such as wool, cotton or silk and also inorganic multifilament yarns such as those composed of metallic or glass fibers in order to achieve special effects. However, the gas jet treatment of the invention is particularly useful when applied to continuous multifilament crimped yarns of synthetic organic thermoplastic polymers in which the amount of crimping falls within a range of about 8 to 25 arcs/cm, preferably about 12 to arcs/cm. With these crimped yarns, the bindings or falsetwisted knots are formed by the very close or solid contact of the individual filaments with each other, and no additional treatment is required to retain the uniformly spaced bindings in the yarn. In other respects, the method and apparatus of the invention can be readily adapted to a wide range of denier and number of filaments in the yarn, although it will obviously be necessary to make a corresponding adjustment in the dimensions of the apparatus and/ or treatment conditions to handle very fine yarns or extremely bulky yarns.

It is most convenient to use air as the gas jet or gas treating stream, e.g. at a temperature of about 2025 C. However, it is also feasible to use any other gas, and if desired, the gas may be heated to an elevated temperature sufficient to fix the yarn by partial softening or melting during the jet treatment. Also, one can apply binders or other special coatings or finishes to the yarn in order to achieve greater adherence of the filaments after the jet treatment. A heated gas may also be used to simultaneously dry a yarn which has been wetted in previous steps with water or an organic solvent.

Although it is most convenient to use a cylindrical jacket and a circular resonance floor and center hole, it will be apparent that these shapes are not critical and that one can also construct the resonating means in other shapes such as elliptical, square or rectangular shapes. Likewise, the jacket slots and bores can assume various shapes and positions provided that they are arranged on center lines which are approximately perpendicular to each other and which intersect at a point which corresponds approximately to the center line of the nozzle axis. These center lines of the jacket slots and bores need not fall in the same plane but are preferably arranged so as to provide a secondary resonance zone in the jacket which includes the normal straight line path of the yarn through the jacket. Also, the position of the nozzle with reference to these jacket slots and bores is preferably adjusted so as to provide a secondary resonance zone which lies at a distance of about 0.2 to 7.5 mm, preferably 0.5 to 6 mm., from the resonance floor.

It will also be apparent that the nozzle and resonating means can be placed in practically any position with reference to the horizontal or vertical and need not be placed only in the generally vertical position with reference to the thread path as shown in the drawings. In this respect, =various references herein to the front, back or side of the apparatus have been made merely for the purpose of convenience.

The above-mentioned and other variations of the method and apparatus of the invention can be easily accomplished by one skilled in this art without departing from the spirit or scope of the invention as defined by the appended claims.

The invention is hereby claimed as follows:

1. A method of producing a voluminous yarn with uniformly spaced bindings which comprises: conducting a continuous multifilament crimped yarn through a partially enclosed secondary resonance zone between two fixed points at which lateral movement of the yarn is prevented while using a yarn feed rate which is about 5 to 50% higher than its draw rate; and laterally oscillating the yarn at a substantially constant frequency between said fixed points under the influence of a jet of gas which is directed substantially perpendicularly to the path of the yarn into a primary resonating'zone which is in direct fluid communication with said secondary resonance zone, thereby producing uniformly spaced bindings along the length of the yarn as it passes through the jet of gas twice in each complete period of oscillation.

2. A method as claimed in claim 1 wherein the feed rate of said yarn is about 10 to 30% higher than its draw rate.

3. A method as claimed in claim 1 wherein the yarn is composed of synthetic organic thermoplastic filaments.

4. Apparatus for producing a voluminous yarn with uniformly spaced bindings which comprises: nozzle means having an opening at one end to eject a jet of gas in a predetermined direction corresponding to the axis of the nozzle; and resonating means including a resonance floor disposed opposite the opening of said nozzle means, said floor having a central opening leading into a primary resonating chamber, and a jacket extending axially from said resonance floor toward said nozzle means to form a secondary resonating chamber, said jacket containing two oppositely disposed slots adapted to receive a continuous yarn in a normal straight line path therebetween which is substantially perpendicular to the nozzle axis and said jacket also containing oppositely disposed openings on a line approximately perpendicular to the straight line path between said slots.

5. Apparatus as claimed in claim 4 wherein the nozzle is adjustable along its axis and is conically shaped toward the opening thereof.

6. Apparatus as claimed in claim 5 wherein said jacket is a cylindrical sleeve which extends from said resonance floor to be positioned concentrically around said nozzle with an annular gap between said sleeve and said nozzle.

7. Apparatus as claimed in claim 4 wherein the opening of the nozzle is a bore with a diameter of about 1 to 5 mm. and the distance between said opening and said resonance floor is about 5 to 15 mm.

8. Apparatus as claimed in claim 4 wherein the opening of the nozzle is a bore With a diameter of about 2 to 4 mm. and the distance between said opening and said resonance floor is about 7 to 12 mm.

9. Apparatus as claimed in claim 4 wherein the slots in said jacket have a width of about 0.5 to 5 :mm. and the UNITED STATES PATENTS 3,123,888 3/1964 Meyers 281 3,125,793 3/1964 Gonsalves 281 3,167,847 2/1965 Gonsalves 281 3,186,155 6/1965 Breen et a1 5714O FOREIGN PATENTS 65 8,465 5/1965 Belgium. 1,064,765 4/ 1967 Great Britain.

JOHN PETRAKES, Primary Examiner.

US. Cl. X.R. 

